#include <iostream>
#include <unistd.h>
#include <cstring>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
enum ExitCode
{
    OK = 0,
    USERAGE_ERR,
    SOCKET_ERR,
    BIND_ERR,
    LISTEN_ERR
};

#define COVN(addr) ((struct sockaddr*)&addr)